#!/usr/bin/env python

#--------------------------------------------------------------------#
# The script                                                         #
#    (1) does a recursive search of directories,                     #
#    (2) looks for a word in all the files (with a given suffix) and #
#    (3) replaces it with another word.                              #
#--------------------------------------------------------------------#

import re
import os
import sys
import time
from optparse import OptionParser
from fileinput import input

#-----------------------------------------
# Function to search and replace in a file
#-----------------------------------------

def searchReplaceFile(fileName, oldWord, newWord):
    data = open(fileName).read()
    open(fileName,"w").write( re.sub(oldWord,newWord,data) )

def process(filename, oldWord, newWord, ext):
    if os.path.isdir(filename):
       return processdir(filename, oldWord, newWord, ext)
    else:
        if os.path.normcase(filename).endswith(ext):
           try:
               searchReplaceFile (filename, oldWord, newWord)
           except IOError, msg:
               sys.stderr.write("Can't open: %s\n" % msg)
               return 1

def processdir(dir, oldWord, newWord, ext):
    try:
        names = os.listdir(dir)
    except os.error, msg:
        sys.stderr.write("Can't list directory: %s\n" % dir)
        return 1
    files = []
    for name in names:
        fn = os.path.join(dir, name)
        process(fn, oldWord, newWord, ext)

def optparse_parsing():
    usage = "Usage: %prog [options] fileSuffix oldWord newWord"
    parser = OptionParser(usage = usage)
    parser.add_option('-i', '--confirm', dest='confirm',
                      action='store_true', default=False,
                      help='Confirm each replacement')
    options, args = parser.parse_args(sys.argv[1:])

    if (len(args) < 3):
       parser.error("Inconrrect number of arguments")

    return options.confirm, args

EXEC_DIR = os.getcwd()
print EXEC_DIR

confirm, args = optparse_parsing()

ext     = args[0]
oldWord = args[1]
newWord = args[2]

process(EXEC_DIR, oldWord, newWord, ext)